Guide wire for medical devices

ABSTRACT

The invention relates to a guide wire for medical devices, which has at least one marking, wherein the guide wire ( 1 ) in its distal area has a spiral ( 11 ), which extends from the distal end of the guide wire ( 1 ) in proximal direction and which has at least two adjoining spiral sections ( 110, 111 ) as markings, which at least at their surface consist of different materials.

The present invention relates to a guide wire for medical devices.

Guide wires are used in particular in minimal invasive surgery and in endoscopy, to deliver medical devices such as catheters or stents over these guide wires into vessels and organs of the patient.

In order to be able to make an exact positioning of the guide wire possible, it is known to provide a marker at the distal end of the guide wire. This marker may for example be a ball of radiopaque material.

In addition, guide wires are known at which markings are provided over the length of the guide wire. These are incorporated into a sheath of the guide wire or are applied onto the sheath. Such a guide wire is for example described in EP 1 208 868 A2. The markings herein are in particular helical color markings, which can be detected through an optical lens of an endoscope.

One disadvantage of these known guide wires is that during interventions, where the guide wire is to be used and which are to be carried out without usage of an endoscope, the detection of the markings is not possible. In addition, due to their helical arrangement, these markings are not suitable for providing the surgeon with an indication of a length or a distance. Moreover, the manufacturing of these guide wires is cumbersome, since a separate application or integration of the markings in the sheath is necessary.

An objective of the present invention is thus to provide a solution, wherein a guide wire can be manufactured in a simple manner and nevertheless is suitable for measuring of lengths or distances in the body of the patient.

The invention is based on the finding that this object can be achieved by integrating a measuring scale into the wire, which consists of areas of a spiral, in particular of areas with different radiopacity.

According to the invention, the object is thus achieved by a guide wire for medical devices, which has at least one marking. The guide wire is characterized in that the guide wire in its distal end has a spiral, which extends from the distal end of the guide wire in proximal direction and which has at least two adjoining spiral sections as markings, wherein at least two of the spiral sections consist of different materials at least at their surface.

A guide wire according to the present invention refers to a medical guide wire, which can be used for introducing medical devices. At least at its distal end the guide wire has a spiral. Distal end in the sense of the present invention refers to the end, which is facing away from the surgeon during the insertion of the guide wire into the patient. Proximal end refers to the end which is opposite of the distal end and which is facing the surgeon and via which the surgeon generally actuates the guide wire, that means moves and positions it. In the distal area of the guide wire the guide wire according to the invention has a spiral. The distal end can be formed by the spiral, in particular by the distal end of the spiral itself. It is, however, also possible that at the distal end of the spiral and thus of the guide wire, a ball is provided which is affixed to the spiral, in particular welded thereto. According to the invention, the spiral extends from the distal end of the guide wire in proximal direction. Preferably, the spiral does not extend over the entire length of the guide wire but has a length which is smaller than ¼ of the overall length of the guide wire. The spiral is preferably attached to a wire of the guide wire, which wire is preferably formed by a solid wire. The spiral can be welded to the distal end of the wire.

According to the invention, the spiral has at least two spiral sections. The spiral sections are adjoining to each other, that means are adjacent to each other. Preferably, the spiral has several spiral sections. In the guide wire according to the invention the spiral sections serves as markings. For this purpose, the individual spiral sections consist at their surface at least of different materials. Herein, in particular, the material of the surface of adjacent spiral sections differs. Spiral sections which are spaced from each other, which are separated by one or more different spiral sections, may according to the invention at least at their surface consist of the same material. The spiral sections, which have different materials at their surface, will hereinafter also be referred to as types of spiral sections. According to the invention at least two types of spiral sections are contained in the spiral. It is, however, also within the scope of the invention to provide three or more types of spiral sections in the spiral. Herein the spiral sections are each arranges such that the material of two spiral sections which are adjacent to each other is always different.

The base material of the individual spiral sections may be the same. In this embodiment, the spiral may be designed as a one-piece. In this case, the individual spiral sections merely differ by the material at their surfaces.

Since the guide wire according to the invention has at least two spiral sections, which at least at their surface consist of different materials and which serve as markings, a number of advantages can be achieved. Firstly, the guide wire can be manufactured in a simple manner since a separate manufacture of a sheath with markings is not necessary. Moreover, a scale is formed at the guide wire due to the markings which are provided at the guide wire itself and which is formed by the spiral sections and which allows for measuring of lengths or distances. As the markings are provided at the distal area of the guide wire, they lie in the introduced state of the guide wire in the immediate vicinity to the vessels or organs which are to be measured and a measurement can thus be carried out reliably. In addition, the materials of adjoingly arranged spiral sections can be chosen such that these have different properties and can thus be displayed to the surgeon differently, since at the spiral sections at least at their surfaces different materials are provided. By detecting the different spiral sections in knowledge of the length of the individual spiral sections, the surgeon can measure a length or a distance within the patient, in particular in a vessel or organ in a simple manner. Finally, the round wire or flat wire, of which the spiral of the guide wire consists, is preferably wound such that the individual windings of the spiral each are in contact with each other. As in the spiral sections of such a spiral, at least at the surface a different material is provided than in adjacent spiral sections, a marking is formed, which lies essentially perpendicular to the longitudinal axis of the guide wire on the circumference of the guide wire. Therefore, the markings according to the invention in comparison to helically provided markings have the further advantage that these are suitable as graduation or can form such a graduation.

According to a preferred embodiment, at least the surface of at least one of the at least two spiral sections consist of a material with lower transmissibility of radiation than the transmissibility of radiation of the material of at least one other of the at least two spiral sections.

If the spiral consists of only two spiral sections, the area at which surface the material has a lower transmissibility for radiation, is arranged spaced from the distal end of the spiral and at the distal end of the spiral a marking for example in the shape of a ball with also lower transmissibility for radiation is provided. Between the ball and the spiral section with lower transmissibility for radiation, a spiral section with higher transmissibility for radiation is provided. In this case the distance between the distal end and the spiral section with lower transmissibility for radiation can serve as a scale for the surgeon during the measurement of a distance.

Preferably, more than two spiral sections are provided. With this embodiment, it is preferred that at least the material at the surface of adjacent spiral sections is different from the other. In particular, in this embodiment, a spiral section having a higher transmissibility for radiation is adjacent to one or two spiral sections having lower transmissibility for radiation and one spiral section with lower transmissibility for radiation is adjacent to one or two spiral sections having lower transmissibility for radiation.

Since at least at the surfaces of the spiral sections materials with different transmissibilities for radiation are provided, the different spiral sections can easily be distinguished from each other by a surgeon during the radiation

According to a preferred embodiment, at least one of the spiral sections has a coating. The coating covers herein preferably at least the outer side of the spiral section, that is the outer surface of this spiral section. Preferably, a spiral section which has a coating is adjacent to uncoated spiral section or to a spiral section having a different coating. The base material of the different spiral sections may be the same.

Since at least one of the spiral sections has a coating, which preferably has properties, which differ from the properties of the base material and/or from the material of the surface of the adjacent spiral sections, it is not necessary to produce one or several spiral sections entirely from a material with the desired properties, in particular low transmissibility for radiation. Since these materials are generally expensive, the provision of a coating is advantageous. In addition, when providing a coating the base material of the spiral section can be chosen depending on other criteria, in particular depending on its flexibility and elasticity. Finally, in this embodiment, the spiral may be made of one piece and the different spiral sections can be formed merely by the coating or omission of coating.

According to a preferred embodiment, the coating, which is provided in at least one spiral section, is formed by vaporization. Vaporization has the advantage that the thickness of the coating can be set equally. In addition, the windings of the spiral, which generally are wound from a round wire or flat wire, can reliably be coated. Finally, during vaporization only a part of the spiral can be coated selectively and thereby a spiral section with appropriate surface properties can be generated. For this purpose the sections of the spiral where no coating is to be generated, can be covered, in particular, shielded by a masc.

According to a preferred embodiment, at least the surface of at least one spiral section consists of a radiopaque material, in particular, of gold, wolfram and/or barium sulfate. Further materials, which can be used as surface of the spiral section(s) with radiopaque material, for example are tantalum, platinum, niobium, palladium, silver or iridium. It is also within the scope of the invention, that the spiral in one or several sections completely consists of such radiopaque material.

According to a preferred embodiment, the spiral sections are separate parts, which are connected to each other at the ends which are facing each other, in particular welded. After having been connected to each other, the spiral parts form the spiral. Herein the distal end of one spiral part is connected to the proximal end of the next adjacent spiral part.

These embodiments have a number of advantages. On the one hand, the length of the individual spiral parts can be reliably set. For this purpose, from two or more raw spirals, which consist of different materials, a piece on the desired length can each be separated, in particular cut off, and the pieces of the different raw spirals are then connected to each other to form the spiral. In addition, this embodiment is of specific advantage for spiral sections which are to have a coating, since the coating can be brought onto the raw spiral on its entire length and a covering of sections of the spiral is not necessary anymore. Furthermore, also spiral sections of different lengths can be manufactured in a simple manner with this embodiment.

The separate spiral parts, which in particular have been cut off from a raw spiral, are connected to each other according to the invention, to thereby form the spiral of the guide wire. The connecting is preferably carried out by welding the spiral parts to each other, wherein the proximal end of a spiral part is welded to the distal end of a further spiral part. As connecting technique for example spot-welding, laser welding and the like can be used. When connecting the spiral parts to form the spiral, in particular only the ends of the round wires or flat wires, which have formed by the separating from the raw spiral, are connected to each other. The windings of adjacent spiral parts which are in contact with each other, in contrast are preferably not welded to each other. Thereby the elasticity and flexibility of the spiral of the guide wire can still be ensured.

According to a preferred embodiment, at least two spiral sections form a scale. For this purpose, preferably at least three spiral parts are provided adjacent to each other. Since the scale is formed at the guidewire itself, the usage of a separate measuring catheter or the like is not necessary.

It is particularly preferable, that the spiral sections have a predetermined length and predetermined distances in the scale. By this layout of the spiral sections, the surgeon, who is aware of the length and the distances, can immediately read a length or a distance for example from an x-ray image. According to one embodiment, for example twenty spiral sections are provided in the scale, wherein these comprise two different types of spiral sections, which are arranged in an alternating manner. The length of the individual spiral sections can be for example 1 cm. It is, however, also within the scope of the invention to produce shorter spiral sections, for example with a length in the range of 0.5 cm to 10 cm.

The spiral sections, according to an embodiment may, however, also have different lengths. For example, it is possible, that the length of the spiral sections continually increases from the distal end of the spiral to the proximal end of the spiral. It is for example also within the scope of the invention, that the spiral has two different types of spiral sections and one type of the spiral sections has a greater length than the other type, wherein the two types of the spiral sections preferably lie alternatingly in the spiral of the guide wire. In any case, a scaling at the spiral of the guide wire can also be established with the spiral sections, which allow a measuring of lengths or distances for the surgeon.

According to a further embodiment, in addition to the different spiral sections as markings in the distal area of the guide wire, at least one indication can be provided at the proximal area of the guide wire, which corresponds to the at least one marking at the distal area, in particular to a spiral section, of the guide wire. The indication can comprise lines, color markings and/or numbers. The indication is preferably provided in the area of the guide wire, which during the intervention, that means in the introduced state of the guide wire in the patient is outside of the body of the patient and is thus visible for the surgeon. By means of this indication, which can also be referred to as reference marking, the measurement, which the surgeon can carry out with the markings in the distal area of the guide wire, can be checked or verified, respectively. Providing a reference marking is, however, not mandatorily necessary for the guide wire according to the invention.

According to a preferred embodiment, the guide wire comprises a wire, which at its distal end has a wire core, onto which at least at the distal end at least a part of the spiral is put on. The spiral is preferably connected, in particular welded, to the wire at proximal end of the wire core. The wire core preferably represents a wire core which is tapered in the distal direction, that means which is conically shaped. The wire core is preferably designed as one piece with the wire shaft, which represents the proximal area of the wire. The wire core can in particular be manufactured by grinding the wire. Subsequently, the spiral is put onto the wire core and is welded to the distal end of the wire shaft. At its proximal end, the spiral thus has an outer diameter, which corresponds to the outer diameter of the wire shaft. In the distal direction, the diameter of the spiral can be unchanging or can decrease.

The invention will now be explained again in detail with reference to the enclosed figures. Therein:

FIG. 1: shows a schematic depiction of an embodiment of the inventive guide wire;

FIG. 2: shows a schematic depiction of an embodiment of the distribution of spiral sections of an embodiment of the spiral of the guide wire according to the present invention;

FIG. 3: shows a schematic depiction of a further embodiment of the guide wire according to the invention;

FIG. 4: shows a schematic depiction of a further embodiment of the guide wire according to the present invention; and

FIG. 5: shows a detailed view of the spiral sections of FIG. 4.

In FIG. 1 an embodiment of the guide wire 1 according to the invention is shown. The guide wire consists of a wire 10 and a spiral 11. The wire 10 has a wire shaft 100 in its proximal area. In the distal area, the wire 10 is formed by a wire core 102. The wire core 102 has a smaller diameter than the wire shaft 100. Between the wire shaft 100 and the wire core 102 a transition area 101 is formed at the wire 10. In the depicted embodiment the transition area 101 is a conical area, over which the diameter of the wire 10 decreases from the wire shaft 100 to the wire core 102.

In the distal area the guide wire 1 is formed at least at its outside by the spiral 11. The proximal end of the spiral 11 is connected, in particular welded, at the transition area 101 with the wire 10. It is, however, also possible to attach, in particular weld, the spiral 11 at the distal end of the wire shaft 100. Therein, the transition area 101 is received in the spiral 11. In the depicted embodiment, a ball 112 is welded to the distal end of the spiral 11. It is, however, also possible to design the guide wire 1 without a ball. The length of the spiral 11 may be larger than the length of the wire core 102. Thereby, the distal area of the guide wire 1 is exclusively formed by the distal area of the spiral 11. The distal area of the spiral 11 designed, as shown in the figures, straight. It is, however, also within the scope of the invention to design the distal end of the spiral 11 bended, for example bended by 180° or curled.

Over the length of the spiral 11 spiral sections 110, 111 are distributed. The spiral sections 110 can for example consist of stainless steel, nitinol or a different material which is suitable for medical technology. The spiral sections 111, to the contrary, may for example be made of the same material as the spiral sections 110 but may be coated, in particular vaporized, at the surface with a radiopaque material, such as wolfram, tantalum, gold, platinum, niobium, palladium, silver or iridium.

According to an embodiment, the spiral 11 is designed as one-piece and the spiral sections 110, 111 are only generated by coating of the parts 111. Alternatively and preferably, it is, however, also possible, that the spiral sections 110, 111 are separate spiral parts, which are welded to each other to form the spiral 11. In that case the spiral sections 111 can for example also entirely consist of a different material than the spiral sections 110, for example of wolfram, gold or a different radiopaque material. In any case, however, also the material of which the spiral parts 111 consist, has an elasticity, which allow for the introduction of the spiral 11 in a vessel or organ of the patient.

The invention is not limited to only two different types of spiral sections 110, 111 being provided. It is rather also within the scope of the invention, that the spiral has more than two different types of spiral sections. Herein, the different types of spiral sections differ preferably by their transmissibility for radiation at least at their surface. Thereby the different types of spiral sections appear differently for example on an x-ray image and are thus easy to distinguish for the surgeon.

The spiral sections 110, 111 are arranged over the length of the spiral 11 in predetermined distances and each have a predetermined length.

In FIG. 2 a schematic depiction of a possible distribution of the spiral sections 110, 111 at an embodiment of the spiral 11 of the guide wire 1 is shown. In this embodiment, at the distal end a spiral section 111 with a higher radiopacity, for example a stainless steel coated with gold or wolfram, is provided. In the proximal direction a spiral sections 111 an also longer spiral sections 110 adjoins, wherein the spiral can for example consist of stainless steel. In the depicted embodiment, five spiral sections 111 of a smaller length follow, between which a section 110 of also smaller length is provided, respectively. The length of the shorter spiral sections 110, 111 is preferably equal. More than the depicted five spiral sections 111 can be provided. Since the shorter spiral sections 110 and 111 are present alternatingly and each have the same length, a scale 113 is formed, which serves the surgeon for measuring distances and lengths. Since the material of the spiral sections 110, 111 in the scale 113 have a different radiopacity, the different spiral sections 110, 111 are easily detectable for the surgeon on an x-ray image.

In FIG. 3 a further embodiment of the guide wire according to the invention is shown. This embodiment differs from the embodiment shown in FIG. 1 only in that the wire core 102 is designed conically and thus tapers towards its distal end. Also the spiral 11 is designed conically in this embodiment. In addition, in the embodiment according to FIG. 3, the transition area 101 is formed as a pitch or step, at which the diameter of the wire shaft 100 decreases to the diameter of the wire core 102 at its proximal end. At this transition area 101 or step, the proximal end of the spiral 11 is attached, in particular glued or welded. The further structure of the guide wire 1 and in particular of the spiral 11 corresponds to the embodiment shown in FIG. 1.

In FIG. 4 a further embodiment of the guide wire 1 according to the invention is shown. The structure of the guide wire 1 corresponds to the structure of the embodiment according to FIG. 1 or 3. In addition, in the embodiment according to FIG. 4 reference markings are provided in the proximal area of the wire 10, the distance of which to each other corresponding to the distances of the spiral sections 111 in the scale 113.

The figures are not to scale. The guide wire 1 can for example have a length of 2.50 m and the length of the spiral can be 50 cm. The spiral sections 110, 111, in particular the spiral sections 110, 111 which form the scale 113, may for example each have a length in the range of 0.5 cm to 10 cm, preferably in the range of 0.5 cm to 1.5 cm. According to an embodiment, the length of the individual spiral sections 110, 111 in the scale are for example 1 cm each.

In FIG. 5 a detailed view of the area of the scale 113 from FIG. 4 is shown. As can be derived from this detailed view A, the spiral sections 110 and 111, which have different surface properties, alternate in the scale 13. The sections 110 and 111 each have the same length in the area of the scale 113 in the depicted embodiment.

The invention is not limited to the depicted embodiments. For example, more or less than the depicted spiral sections 110, 111 may be arranged in the scale 113. In addition, also further spiral sections, which have surface property, in particular radiopacity, different to the spiral sections 110, 111 can be integrated in the scale 113. Furthermore, for example the lengths of the individual spiral sections 110, 111 in the scale 113 may increase in one direction. For example, spiral sections 110, 111 with a shorter length can be arranged in the distal area of the scale 113 and the length of the respective spiral sections 110, 111 can increase gradually in the proximal direction in the scale 113.

The present invention thus provides a solution, wherein a guide wire can be manufactured in a simple manner but nevertheless is suitable for measuring lengths or distances in the body of a patient. Therein, in particular a measuring scale is integrated in the wire, which consists of parts of the spiral of the guide wire and in particular of spiral sections with different radiopacity.

Preferably, a spiral of the guide wire according to the invention is composed of at least two spiral parts. The spiral parts are preferably glued or welded to each other. The welding can preferably be carried out by means of laser. According to a preferred embodiment, at least in the distal area of the guide wire, at least two, preferably at least three spiral parts are attached to each other in axial direction. Therein the spiral parts may each have the same length. According to a further embodiment, the length of the spiral parts increases in proximal or distal direction.

The present invention has a number of advantages. In particular it is possible with the present invention to conduct an intravascular measuring of vessels and/or organs and in particular to determine their length. In addition, for example vessel distances can be determined. This is for example of importance for determining the length of a prosthesis which is to be inserted into the vessel. Therein and in other steps, which necessitate the determination of the length of a vessel and/or organ and/or of a vessel distance, the usage of separate measuring catheters is no longer necessary when using the guide wire according to the invention. Instead the guide wire, via which the prosthesis or other medical device is guided, can simultaneously be used for measuring. Thereby the entire intervention at the patient is simplified and the duration of the intervention is shortened.

Finally, the manufacturing of the guide wire is simplified, as the spiral, at which the spiral sections are formed, can be manufactured beforehand and subsequently only has to be attached to the wire of the guide wire. Furthermore in an embodiment, wherein the spiral sections are formed by separate spiral parts, the length of the spiral parts can easily and reliably be established by cutting the separate spiral sections in the corresponding length off of a raw spiral.

LIST OF REFERENCE NUMBERS

-   1 guide wire -   10 wire -   100 wire shaft -   101 transition area -   102 wire core -   103 reference marking -   11 spiral -   110 spiral section -   111 spiral section -   112 ball -   113 scale 

1. Guide wire for medical devices, which has at least one marking, characterized in that the guide wire in its distal area has a spiral, which extends from the distal end of the guide wire in proximal direction and which has at least two adjoining spiral sections as markings, which at least at their surface consist of different materials.
 2. Guide wire according to claim 1, characterized in that at least the surface of at least one of the at least two spiral sections consists of a material with lower transmissibility for radiation than the transmissibility for radiation of the material of at least one further spiral section of the at least two spiral sections.
 3. Guide wire according to claim 1, characterized in that at least one of the spiral sections has a coating.
 4. Guide wire according to claim 3, characterized in that the coating is vaporized.
 5. Guide wire according to claim 1, characterized in that at least the surface of at least one spiral section consists of a radiopaque material, in particular of gold and/or barium sulfate.
 6. Guide wire according to claim 1, characterized in that the spiral sections are separate parts, which are attached to each other at their ends which are facing towards each other, in particular are welded.
 7. Guide wire according to claim 1, characterized in that at least two spiral sections form a scale.
 8. Guide wire according to claim 7, characterized in that the spiral sections in the scale have a predetermined length and predetermined distances.
 9. Guide wire according to claim 1, characterized in that the at least two spiral sections have different lengths.
 10. Guide wire according to claim 1, characterized in that the guide wire has at least one indication at its proximal area, which corresponds to the at least one marking at the distal area of the guide wire.
 11. Guide wire according to claim 1, characterized in that the guide wire comprises a wire, which has a wire core at its distal end, on which at least at the distal end at least a part of the spiral is put on. 